Final answer:
The correct order of the protective layers above the brain, or meninges, is Dura Mater, Arachnoid Mater, and Pia Mater. The Dura Mater is the tough outer layer, the Arachnoid Mater is the web-like middle layer, and the Pia Mater is the delicate inner layer that clings to the brain's surface.
Step-by-step explanation:
The layers of protection above the brain, known as the meninges, consist of three distinct membranous layers. These provide a critical role in safeguarding the central nervous system (CNS), which includes both the brain and spinal cord. The correct order of these meningeal layers from outermost to innermost is: Dura Mater, Arachnoid Mater, and Pia Mater.
The outermost layer is the Dura Mater, a tough and durable membrane that encases the CNS and anchors to the inner surface of the skull and vertebral canal. The middle layer is the Arachnoid Mater, which resembles a spider web with its fine strands (trabeculae) and defines a sac-like enclosure around the CNS. Lastly, the innermost layer touching the brain and spinal cord directly is the Pia Mater, a delicate fibrous membrane that adheres closely to every contour of the brain.
Hence, the correct sequence is option (d): Dura Mater - Arachnoid Mater - Pia Mater.